// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Copyright (c) by Uros Bizjak <uros@kss-loka.si>
 *
 *  Midi synth routines for OPL2/OPL3/OPL4 FM
 */

#undef DEBUG_ALLOC
#undef DEBUG_MIDI

#include "opl3_voice.h"
#include <sound/asoundef.h>

static void snd_opl3_note_off_unsafe(void *p, int note, int vel,
                                     struct snd_midi_channel *chan);
/*
 * The next table looks magical, but it certainly is not. Its values have
 * been calculated as table[i]=8*log(i/64)/log(2) with an obvious exception
 * for i=0. This log-table converts a linear volume-scaling (0..127) to a
 * logarithmic scaling as present in the FM-synthesizer chips. so :    Volume
 * 64 =  0 db = relative volume  0 and:    Volume 32 = -6 db = relative
 * volume -8 it was implemented as a table because it is only 128 bytes and
 * it saves a lot of log() calculations. (Rob Hooft <hooft@chem.ruu.nl>)
 */

static const char opl3_volume_table[128] =
{
        -63, -48, -40, -35, -32, -29, -27, -26,
        -24, -23, -21, -20, -19, -18, -18, -17,
        -16, -15, -15, -14, -13, -13, -12, -12,
        -11, -11, -10, -10, -10, -9, -9, -8,
        -8, -8, -7, -7, -7, -6, -6, -6,
        -5, -5, -5, -5, -4, -4, -4, -4,
        -3, -3, -3, -3, -2, -2, -2, -2,
        -2, -1, -1, -1, -1, 0, 0, 0,
        0, 0, 0, 1, 1, 1, 1, 1,
        1, 2, 2, 2, 2, 2, 2, 2,
        3, 3, 3, 3, 3, 3, 3, 4,
        4, 4, 4, 4, 4, 4, 4, 5,
        5, 5, 5, 5, 5, 5, 5, 5,
        6, 6, 6, 6, 6, 6, 6, 6,
        6, 7, 7, 7, 7, 7, 7, 7,
        7, 7, 7, 8, 8, 8, 8, 8
};

void snd_opl3_calc_volume(unsigned char *volbyte, int vel,
                          struct snd_midi_channel *chan)
{
        int oldvol, newvol, n;
        int volume;

        volume = (vel * chan->gm_volume * chan->gm_expression) / (127*127);
        if (volume > 127)
                volume = 127;

        oldvol = OPL3_TOTAL_LEVEL_MASK - (*volbyte & OPL3_TOTAL_LEVEL_MASK);

        newvol = opl3_volume_table[volume] + oldvol;
        if (newvol > OPL3_TOTAL_LEVEL_MASK)
                newvol = OPL3_TOTAL_LEVEL_MASK;
        else if (newvol < 0)
                newvol = 0;

        n = OPL3_TOTAL_LEVEL_MASK - (newvol & OPL3_TOTAL_LEVEL_MASK);

        *volbyte = (*volbyte & OPL3_KSL_MASK) | (n & OPL3_TOTAL_LEVEL_MASK);
}

/*
 * Converts the note frequency to block and fnum values for the FM chip
 */
static const short opl3_note_table[16] =
{
        305, 323,       /* for pitch bending, -2 semitones */
        343, 363, 385, 408, 432, 458, 485, 514, 544, 577, 611, 647,
        686, 726        /* for pitch bending, +2 semitones */
};

static void snd_opl3_calc_pitch(unsigned char *fnum, unsigned char *blocknum,
                                int note, struct snd_midi_channel *chan)
{
        int block = ((note / 12) & 0x07) - 1;
        int idx = (note % 12) + 2;
        int freq;

        if (chan->midi_pitchbend) {
                int pitchbend = chan->midi_pitchbend;
                int segment;

                if (pitchbend < -0x2000)
                        pitchbend = -0x2000;
                if (pitchbend > 0x1FFF)
                        pitchbend = 0x1FFF;

                segment = pitchbend / 0x1000;
                freq = opl3_note_table[idx+segment];
                freq += ((opl3_note_table[idx+segment+1] - freq) *
                         (pitchbend % 0x1000)) / 0x1000;
        } else {
                freq = opl3_note_table[idx];
        }

        *fnum = (unsigned char) freq;
        *blocknum = ((freq >> 8) & OPL3_FNUM_HIGH_MASK) |
                ((block << 2) & OPL3_BLOCKNUM_MASK);
}


#ifdef DEBUG_ALLOC
static void debug_alloc(struct snd_opl3 *opl3, char *s, int voice) {
        int i;
        char *str = "x.24";

        printk(KERN_DEBUG "time %.5i: %s [%.2i]: ", opl3->use_time, s, voice);
        for (i = 0; i < opl3->max_voices; i++)
                printk(KERN_CONT "%c", *(str + opl3->voices[i].state + 1));
        printk(KERN_CONT "\n");
}
#endif

/*
 * Get a FM voice (channel) to play a note on.
 */
static int opl3_get_voice(struct snd_opl3 *opl3, int instr_4op,
                          struct snd_midi_channel *chan) {
        int chan_4op_1;         /* first voice for 4op instrument */
        int chan_4op_2;         /* second voice for 4op instrument */

        struct snd_opl3_voice *vp, *vp2;
        unsigned int voice_time;
        int i;

#ifdef DEBUG_ALLOC
        char *alloc_type[3] = { "FREE     ", "CHEAP    ", "EXPENSIVE" };
#endif

        /* This is our "allocation cost" table */
        enum {
                FREE = 0, CHEAP, EXPENSIVE, END
        };

        /* Keeps track of what we are finding */
        struct best {
                unsigned int time;
                int voice;
        } best[END];
        struct best *bp;

        for (i = 0; i < END; i++) {
                best[i].time = (unsigned int)(-1); /* XXX MAX_?INT really */
                best[i].voice = -1;
        }

        /* Look through all the channels for the most suitable. */
        for (i = 0; i < opl3->max_voices; i++) {
                vp = &opl3->voices[i];

                if (vp->state == SNDRV_OPL3_ST_NOT_AVAIL)
                  /* skip unavailable channels, allocated by
                     drum voices or by bounded 4op voices) */
                        continue;

                voice_time = vp->time;
                bp = best;

                chan_4op_1 = ((i < 3) || (i > 8 && i < 12));
                chan_4op_2 = ((i > 2 && i < 6) || (i > 11 && i < 15));
                if (instr_4op) {
                        /* allocate 4op voice */
                        /* skip channels unavailable to 4op instrument */
                        if (!chan_4op_1)
                                continue;

                        if (vp->state)
                                /* kill one voice, CHEAP */
                                bp++;
                        /* get state of bounded 2op channel
                           to be allocated for 4op instrument */
                        vp2 = &opl3->voices[i + 3];
                        if (vp2->state == SNDRV_OPL3_ST_ON_2OP) {
                                /* kill two voices, EXPENSIVE */
                                bp++;
                                voice_time = (voice_time > vp->time) ?
                                        voice_time : vp->time;
                        }
                } else {
                        /* allocate 2op voice */
                        if ((chan_4op_1) || (chan_4op_2))
                                /* use bounded channels for 2op, CHEAP */
                                bp++;
                        else if (vp->state)
                                /* kill one voice on 2op channel, CHEAP */
                                bp++;
                        /* raise kill cost to EXPENSIVE for all channels */
                        if (vp->state)
                                bp++;
                }
                if (voice_time < bp->time) {
                        bp->time = voice_time;
                        bp->voice = i;
                }
        }

        for (i = 0; i < END; i++) {
                if (best[i].voice >= 0) {
#ifdef DEBUG_ALLOC
                        printk(KERN_DEBUG "%s %iop allocation on voice %i\n",
                               alloc_type[i], instr_4op ? 4 : 2,
                               best[i].voice);
#endif
                        return best[i].voice;
                }
        }
        /* not found */
        return -1;
}

/* ------------------------------ */

/*
 * System timer interrupt function
 */
void snd_opl3_timer_func(struct timer_list *t)
{

        struct snd_opl3 *opl3 = from_timer(opl3, t, tlist);
        unsigned long flags;
        int again = 0;
        int i;

        spin_lock_irqsave(&opl3->voice_lock, flags);
        for (i = 0; i < opl3->max_voices; i++) {
                struct snd_opl3_voice *vp = &opl3->voices[i];
                if (vp->state > 0 && vp->note_off_check) {
                        if (vp->note_off == jiffies)
                                snd_opl3_note_off_unsafe(opl3, vp->note, 0,
                                                         vp->chan);
                        else
                                again++;
                }
        }
        spin_unlock_irqrestore(&opl3->voice_lock, flags);

        spin_lock_irqsave(&opl3->sys_timer_lock, flags);
        if (again)
                mod_timer(&opl3->tlist, jiffies + 1);   /* invoke again */
        else
                opl3->sys_timer_status = 0;
        spin_unlock_irqrestore(&opl3->sys_timer_lock, flags);
}

/*
 * Start system timer
 */
static void snd_opl3_start_timer(struct snd_opl3 *opl3)
{
        unsigned long flags;
        spin_lock_irqsave(&opl3->sys_timer_lock, flags);
        if (! opl3->sys_timer_status) {
                mod_timer(&opl3->tlist, jiffies + 1);
                opl3->sys_timer_status = 1;
        }
        spin_unlock_irqrestore(&opl3->sys_timer_lock, flags);
}

/* ------------------------------ */


static const int snd_opl3_oss_map[MAX_OPL3_VOICES] = {
        0, 1, 2, 9, 10, 11, 6, 7, 8, 15, 16, 17, 3, 4 ,5, 12, 13, 14
};

/*
 * Start a note.
 */
void snd_opl3_note_on(void *p, int note, int vel, struct snd_midi_channel *chan)
{
        struct snd_opl3 *opl3;
        int instr_4op;

        int voice;
        struct snd_opl3_voice *vp, *vp2;
        unsigned short connect_mask;
        unsigned char connection;
        unsigned char vol_op[4];

        int extra_prg = 0;

        unsigned short reg_side;
        unsigned char op_offset;
        unsigned char voice_offset;
        unsigned short opl3_reg;
        unsigned char reg_val;
        unsigned char prg, bank;

        int key = note;
        unsigned char fnum, blocknum;
        int i;

        struct fm_patch *patch;
        struct fm_instrument *fm;
        unsigned long flags;

        opl3 = p;

#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "Note on, ch %i, inst %i, note %i, vel %i\n",
                   chan->number, chan->midi_program, note, vel);
#endif

        /* in SYNTH mode, application takes care of voices */
        /* in SEQ mode, drum voice numbers are notes on drum channel */
        if (opl3->synth_mode == SNDRV_OPL3_MODE_SEQ) {
                if (chan->drum_channel) {
                        /* percussion instruments are located in bank 128 */
                        bank = 128;
                        prg = note;
                } else {
                        bank = chan->gm_bank_select;
                        prg = chan->midi_program;
                }
        } else {
                /* Prepare for OSS mode */
                if (chan->number >= MAX_OPL3_VOICES)
                        return;

                /* OSS instruments are located in bank 127 */
                bank = 127;
                prg = chan->midi_program;
        }

        spin_lock_irqsave(&opl3->voice_lock, flags);

        if (use_internal_drums) {
                snd_opl3_drum_switch(opl3, note, vel, 1, chan);
                spin_unlock_irqrestore(&opl3->voice_lock, flags);
                return;
        }

 __extra_prg:
        patch = snd_opl3_find_patch(opl3, prg, bank, 0);
        if (!patch) {
                spin_unlock_irqrestore(&opl3->voice_lock, flags);
                return;
        }

        fm = &patch->inst;
        switch (patch->type) {
        case FM_PATCH_OPL2:
                instr_4op = 0;
                break;
        case FM_PATCH_OPL3:
                if (opl3->hardware >= OPL3_HW_OPL3) {
                        instr_4op = 1;
                        break;
                }
                /* fall through */
        default:
                spin_unlock_irqrestore(&opl3->voice_lock, flags);
                return;
        }
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "  --> OPL%i instrument: %s\n",
                   instr_4op ? 3 : 2, patch->name);
#endif
        /* in SYNTH mode, application takes care of voices */
        /* in SEQ mode, allocate voice on free OPL3 channel */
        if (opl3->synth_mode == SNDRV_OPL3_MODE_SEQ) {
                voice = opl3_get_voice(opl3, instr_4op, chan);
        } else {
                /* remap OSS voice */
                voice = snd_opl3_oss_map[chan->number];         
        }

        if (voice < 0) {
                spin_unlock_irqrestore(&opl3->voice_lock, flags);
                return;
        }

        if (voice < MAX_OPL2_VOICES) {
                /* Left register block for voices 0 .. 8 */
                reg_side = OPL3_LEFT;
                voice_offset = voice;
                connect_mask = (OPL3_LEFT_4OP_0 << voice_offset) & 0x07;
        } else {
                /* Right register block for voices 9 .. 17 */
                reg_side = OPL3_RIGHT;
                voice_offset = voice - MAX_OPL2_VOICES;
                connect_mask = (OPL3_RIGHT_4OP_0 << voice_offset) & 0x38;
        }

        /* kill voice on channel */
        vp = &opl3->voices[voice];
        if (vp->state > 0) {
                opl3_reg = reg_side | (OPL3_REG_KEYON_BLOCK + voice_offset);
                reg_val = vp->keyon_reg & ~OPL3_KEYON_BIT;
                opl3->command(opl3, opl3_reg, reg_val);
        }
        if (instr_4op) {
                vp2 = &opl3->voices[voice + 3];
                if (vp->state > 0) {
                        opl3_reg = reg_side | (OPL3_REG_KEYON_BLOCK +
                                               voice_offset + 3);
                        reg_val = vp->keyon_reg & ~OPL3_KEYON_BIT;
                        opl3->command(opl3, opl3_reg, reg_val);
                }
        }

        /* set connection register */
        if (instr_4op) {
                if ((opl3->connection_reg ^ connect_mask) & connect_mask) {
                        opl3->connection_reg |= connect_mask;
                        /* set connection bit */
                        opl3_reg = OPL3_RIGHT | OPL3_REG_CONNECTION_SELECT;
                        opl3->command(opl3, opl3_reg, opl3->connection_reg);
                }
        } else {
                if ((opl3->connection_reg ^ ~connect_mask) & connect_mask) {
                        opl3->connection_reg &= ~connect_mask;
                        /* clear connection bit */
                        opl3_reg = OPL3_RIGHT | OPL3_REG_CONNECTION_SELECT;
                        opl3->command(opl3, opl3_reg, opl3->connection_reg);
                }
        }

#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "  --> setting OPL3 connection: 0x%x\n",
                   opl3->connection_reg);
#endif
        /*
         * calculate volume depending on connection
         * between FM operators (see include/opl3.h)
         */
        for (i = 0; i < (instr_4op ? 4 : 2); i++)
                vol_op[i] = fm->op[i].ksl_level;

        connection = fm->feedback_connection[0] & 0x01;
        if (instr_4op) {
                connection <<= 1;
                connection |= fm->feedback_connection[1] & 0x01;

                snd_opl3_calc_volume(&vol_op[3], vel, chan);
                switch (connection) {
                case 0x03:
                        snd_opl3_calc_volume(&vol_op[2], vel, chan);
                        /* fallthru */
                case 0x02:
                        snd_opl3_calc_volume(&vol_op[0], vel, chan);
                        break;
                case 0x01:
                        snd_opl3_calc_volume(&vol_op[1], vel, chan);
                }
        } else {
                snd_opl3_calc_volume(&vol_op[1], vel, chan);
                if (connection)
                        snd_opl3_calc_volume(&vol_op[0], vel, chan);
        }

        /* Program the FM voice characteristics */
        for (i = 0; i < (instr_4op ? 4 : 2); i++) {
#ifdef DEBUG_MIDI
                snd_printk(KERN_DEBUG "  --> programming operator %i\n", i);
#endif
                op_offset = snd_opl3_regmap[voice_offset][i];

                /* Set OPL3 AM_VIB register of requested voice/operator */ 
                reg_val = fm->op[i].am_vib;
                opl3_reg = reg_side | (OPL3_REG_AM_VIB + op_offset);
                opl3->command(opl3, opl3_reg, reg_val);

                /* Set OPL3 KSL_LEVEL register of requested voice/operator */ 
                reg_val = vol_op[i];
                opl3_reg = reg_side | (OPL3_REG_KSL_LEVEL + op_offset);
                opl3->command(opl3, opl3_reg, reg_val);

                /* Set OPL3 ATTACK_DECAY register of requested voice/operator */ 
                reg_val = fm->op[i].attack_decay;
                opl3_reg = reg_side | (OPL3_REG_ATTACK_DECAY + op_offset);
                opl3->command(opl3, opl3_reg, reg_val);

                /* Set OPL3 SUSTAIN_RELEASE register of requested voice/operator */ 
                reg_val = fm->op[i].sustain_release;
                opl3_reg = reg_side | (OPL3_REG_SUSTAIN_RELEASE + op_offset);
                opl3->command(opl3, opl3_reg, reg_val);

                /* Select waveform */
                reg_val = fm->op[i].wave_select;
                opl3_reg = reg_side | (OPL3_REG_WAVE_SELECT + op_offset);
                opl3->command(opl3, opl3_reg, reg_val);
        }

        /* Set operator feedback and 2op inter-operator connection */
        reg_val = fm->feedback_connection[0];
        /* Set output voice connection */
        reg_val |= OPL3_STEREO_BITS;
        if (chan->gm_pan < 43)
                reg_val &= ~OPL3_VOICE_TO_RIGHT;
        if (chan->gm_pan > 85)
                reg_val &= ~OPL3_VOICE_TO_LEFT;
        opl3_reg = reg_side | (OPL3_REG_FEEDBACK_CONNECTION + voice_offset);
        opl3->command(opl3, opl3_reg, reg_val);

        if (instr_4op) {
                /* Set 4op inter-operator connection */
                reg_val = fm->feedback_connection[1] & OPL3_CONNECTION_BIT;
                /* Set output voice connection */
                reg_val |= OPL3_STEREO_BITS;
                if (chan->gm_pan < 43)
                        reg_val &= ~OPL3_VOICE_TO_RIGHT;
                if (chan->gm_pan > 85)
                        reg_val &= ~OPL3_VOICE_TO_LEFT;
                opl3_reg = reg_side | (OPL3_REG_FEEDBACK_CONNECTION +
                                       voice_offset + 3);
                opl3->command(opl3, opl3_reg, reg_val);
        }

        /*
         * Special treatment of percussion notes for fm:
         * Requested pitch is really program, and pitch for
         * device is whatever was specified in the patch library.
         */
        if (fm->fix_key)
                note = fm->fix_key;
        /*
         * use transpose if defined in patch library
         */
        if (fm->trnsps)
                note += (fm->trnsps - 64);

        snd_opl3_calc_pitch(&fnum, &blocknum, note, chan);

        /* Set OPL3 FNUM_LOW register of requested voice */
        opl3_reg = reg_side | (OPL3_REG_FNUM_LOW + voice_offset);
        opl3->command(opl3, opl3_reg, fnum);

        opl3->voices[voice].keyon_reg = blocknum;

        /* Set output sound flag */
        blocknum |= OPL3_KEYON_BIT;

#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "  --> trigger voice %i\n", voice);
#endif
        /* Set OPL3 KEYON_BLOCK register of requested voice */ 
        opl3_reg = reg_side | (OPL3_REG_KEYON_BLOCK + voice_offset);
        opl3->command(opl3, opl3_reg, blocknum);

        /* kill note after fixed duration (in centiseconds) */
        if (fm->fix_dur) {
                opl3->voices[voice].note_off = jiffies +
                        (fm->fix_dur * HZ) / 100;
                snd_opl3_start_timer(opl3);
                opl3->voices[voice].note_off_check = 1;
        } else
                opl3->voices[voice].note_off_check = 0;

        /* get extra pgm, but avoid possible loops */
        extra_prg = (extra_prg) ? 0 : fm->modes;

        /* do the bookkeeping */
        vp->time = opl3->use_time++;
        vp->note = key;
        vp->chan = chan;

        if (instr_4op) {
                vp->state = SNDRV_OPL3_ST_ON_4OP;

                vp2 = &opl3->voices[voice + 3];
                vp2->time = opl3->use_time++;
                vp2->note = key;
                vp2->chan = chan;
                vp2->state = SNDRV_OPL3_ST_NOT_AVAIL;
        } else {
                if (vp->state == SNDRV_OPL3_ST_ON_4OP) {
                        /* 4op killed by 2op, release bounded voice */
                        vp2 = &opl3->voices[voice + 3];
                        vp2->time = opl3->use_time++;
                        vp2->state = SNDRV_OPL3_ST_OFF;
                }
                vp->state = SNDRV_OPL3_ST_ON_2OP;
        }

#ifdef DEBUG_ALLOC
        debug_alloc(opl3, "note on ", voice);
#endif

        /* allocate extra program if specified in patch library */
        if (extra_prg) {
                if (extra_prg > 128) {
                        bank = 128;
                        /* percussions start at 35 */
                        prg = extra_prg - 128 + 35 - 1;
                } else {
                        bank = 0;
                        prg = extra_prg - 1;
                }
#ifdef DEBUG_MIDI
                snd_printk(KERN_DEBUG " *** allocating extra program\n");
#endif
                goto __extra_prg;
        }
        spin_unlock_irqrestore(&opl3->voice_lock, flags);
}

static void snd_opl3_kill_voice(struct snd_opl3 *opl3, int voice)
{
        unsigned short reg_side;
        unsigned char voice_offset;
        unsigned short opl3_reg;

        struct snd_opl3_voice *vp, *vp2;

        if (snd_BUG_ON(voice >= MAX_OPL3_VOICES))
                return;

        vp = &opl3->voices[voice];
        if (voice < MAX_OPL2_VOICES) {
                /* Left register block for voices 0 .. 8 */
                reg_side = OPL3_LEFT;
                voice_offset = voice;
        } else {
                /* Right register block for voices 9 .. 17 */
                reg_side = OPL3_RIGHT;
                voice_offset = voice - MAX_OPL2_VOICES;
        }

        /* kill voice */
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "  --> kill voice %i\n", voice);
#endif
        opl3_reg = reg_side | (OPL3_REG_KEYON_BLOCK + voice_offset);
        /* clear Key ON bit */
        opl3->command(opl3, opl3_reg, vp->keyon_reg);

        /* do the bookkeeping */
        vp->time = opl3->use_time++;

        if (vp->state == SNDRV_OPL3_ST_ON_4OP) {
                vp2 = &opl3->voices[voice + 3];

                vp2->time = opl3->use_time++;
                vp2->state = SNDRV_OPL3_ST_OFF;
        }
        vp->state = SNDRV_OPL3_ST_OFF;
#ifdef DEBUG_ALLOC
        debug_alloc(opl3, "note off", voice);
#endif

}

/*
 * Release a note in response to a midi note off.
 */
static void snd_opl3_note_off_unsafe(void *p, int note, int vel,
                                     struct snd_midi_channel *chan)
{
        struct snd_opl3 *opl3;

        int voice;
        struct snd_opl3_voice *vp;

        opl3 = p;

#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "Note off, ch %i, inst %i, note %i\n",
                   chan->number, chan->midi_program, note);
#endif

        if (opl3->synth_mode == SNDRV_OPL3_MODE_SEQ) {
                if (chan->drum_channel && use_internal_drums) {
                        snd_opl3_drum_switch(opl3, note, vel, 0, chan);
                        return;
                }
                /* this loop will hopefully kill all extra voices, because
                   they are grouped by the same channel and note values */
                for (voice = 0; voice < opl3->max_voices; voice++) {
                        vp = &opl3->voices[voice];
                        if (vp->state > 0 && vp->chan == chan && vp->note == note) {
                                snd_opl3_kill_voice(opl3, voice);
                        }
                }
        } else {
                /* remap OSS voices */
                if (chan->number < MAX_OPL3_VOICES) {
                        voice = snd_opl3_oss_map[chan->number];         
                        snd_opl3_kill_voice(opl3, voice);
                }
        }
}

void snd_opl3_note_off(void *p, int note, int vel,
                       struct snd_midi_channel *chan)
{
        struct snd_opl3 *opl3 = p;
        unsigned long flags;

        spin_lock_irqsave(&opl3->voice_lock, flags);
        snd_opl3_note_off_unsafe(p, note, vel, chan);
        spin_unlock_irqrestore(&opl3->voice_lock, flags);
}

/*
 * key pressure change
 */
void snd_opl3_key_press(void *p, int note, int vel, struct snd_midi_channel *chan)
{
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "Key pressure, ch#: %i, inst#: %i\n",
                   chan->number, chan->midi_program);
#endif
}

/*
 * terminate note
 */
void snd_opl3_terminate_note(void *p, int note, struct snd_midi_channel *chan)
{
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "Terminate note, ch#: %i, inst#: %i\n",
                   chan->number, chan->midi_program);
#endif
}

static void snd_opl3_update_pitch(struct snd_opl3 *opl3, int voice)
{
        unsigned short reg_side;
        unsigned char voice_offset;
        unsigned short opl3_reg;

        unsigned char fnum, blocknum;

        struct snd_opl3_voice *vp;

        if (snd_BUG_ON(voice >= MAX_OPL3_VOICES))
                return;

        vp = &opl3->voices[voice];
        if (vp->chan == NULL)
                return; /* not allocated? */

        if (voice < MAX_OPL2_VOICES) {
                /* Left register block for voices 0 .. 8 */
                reg_side = OPL3_LEFT;
                voice_offset = voice;
        } else {
                /* Right register block for voices 9 .. 17 */
                reg_side = OPL3_RIGHT;
                voice_offset = voice - MAX_OPL2_VOICES;
        }

        snd_opl3_calc_pitch(&fnum, &blocknum, vp->note, vp->chan);

        /* Set OPL3 FNUM_LOW register of requested voice */
        opl3_reg = reg_side | (OPL3_REG_FNUM_LOW + voice_offset);
        opl3->command(opl3, opl3_reg, fnum);

        vp->keyon_reg = blocknum;

        /* Set output sound flag */
        blocknum |= OPL3_KEYON_BIT;

        /* Set OPL3 KEYON_BLOCK register of requested voice */ 
        opl3_reg = reg_side | (OPL3_REG_KEYON_BLOCK + voice_offset);
        opl3->command(opl3, opl3_reg, blocknum);

        vp->time = opl3->use_time++;
}

/*
 * Update voice pitch controller
 */
static void snd_opl3_pitch_ctrl(struct snd_opl3 *opl3, struct snd_midi_channel *chan)
{
        int voice;
        struct snd_opl3_voice *vp;

        unsigned long flags;

        spin_lock_irqsave(&opl3->voice_lock, flags);

        if (opl3->synth_mode == SNDRV_OPL3_MODE_SEQ) {
                for (voice = 0; voice < opl3->max_voices; voice++) {
                        vp = &opl3->voices[voice];
                        if (vp->state > 0 && vp->chan == chan) {
                                snd_opl3_update_pitch(opl3, voice);
                        }
                }
        } else {
                /* remap OSS voices */
                if (chan->number < MAX_OPL3_VOICES) {
                        voice = snd_opl3_oss_map[chan->number];         
                        snd_opl3_update_pitch(opl3, voice);
                }
        }
        spin_unlock_irqrestore(&opl3->voice_lock, flags);
}

/*
 * Deal with a controller type event.  This includes all types of
 * control events, not just the midi controllers
 */
void snd_opl3_control(void *p, int type, struct snd_midi_channel *chan)
{
        struct snd_opl3 *opl3;

        opl3 = p;
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "Controller, TYPE = %i, ch#: %i, inst#: %i\n",
                   type, chan->number, chan->midi_program);
#endif

        switch (type) {
        case MIDI_CTL_MSB_MODWHEEL:
                if (chan->control[MIDI_CTL_MSB_MODWHEEL] > 63)
                        opl3->drum_reg |= OPL3_VIBRATO_DEPTH;
                else 
                        opl3->drum_reg &= ~OPL3_VIBRATO_DEPTH;
                opl3->command(opl3, OPL3_LEFT | OPL3_REG_PERCUSSION,
                                 opl3->drum_reg);
                break;
        case MIDI_CTL_E2_TREMOLO_DEPTH:
                if (chan->control[MIDI_CTL_E2_TREMOLO_DEPTH] > 63)
                        opl3->drum_reg |= OPL3_TREMOLO_DEPTH;
                else 
                        opl3->drum_reg &= ~OPL3_TREMOLO_DEPTH;
                opl3->command(opl3, OPL3_LEFT | OPL3_REG_PERCUSSION,
                                 opl3->drum_reg);
                break;
        case MIDI_CTL_PITCHBEND:
                snd_opl3_pitch_ctrl(opl3, chan);
                break;
        }
}

/*
 * NRPN events
 */
void snd_opl3_nrpn(void *p, struct snd_midi_channel *chan,
                   struct snd_midi_channel_set *chset)
{
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "NRPN, ch#: %i, inst#: %i\n",
                   chan->number, chan->midi_program);
#endif
}

/*
 * receive sysex
 */
void snd_opl3_sysex(void *p, unsigned char *buf, int len,
                    int parsed, struct snd_midi_channel_set *chset)
{
#ifdef DEBUG_MIDI
        snd_printk(KERN_DEBUG "SYSEX\n");
#endif
}